1. Field of the Invention
The present invention relates to an improvement in the configuration of corona dischargers employed in air-purifying devices as a result of which the discharger can generate coronas more effectively and which makes it more easy to assemble than conventional corona dischargers.
2. Description of the Prior Art
The term "corona discharge" refers to the surface discharge phenomenon between a high-voltage electrode and a low-voltage electrode which can be used to ionize air or gases passing between these two electrodes. In practical applications, corona discharges can be employed to purify air and generate ozone. Proper insulation of the high-voltage and low-voltage electrodes is the most important consideration in the configuration of corona dischargers. If the insulation is improper, the discharge of electricity can become localized, resulting in failure to produce a corona. Today's corona dischargers employed in air-purifying devices typically use a configuration such as that disclosed in the Republic of China Patent No. 78212629. Specifically, as shown in FIG. 1, the device consists of a ground casing 1 equipped with one or more slots separated by ground plates 10, with the high-voltage plates 12 inserted into these slots, thereby forming a system in which the ground plate 10 and high-voltage plate 12 are arranged in an alternate order. The high-voltage plate 12 consists of a pair of insulating plates 121 and 121' which sandwich an electrode piece 122. The gap 124 formed between the insulating plates 121 and 121' is sealed with an insulating adhesive material. In order to prevent the formation of cracks due to aging of the insulating adhesive material after the device has been in use for a period of time, an insulating cap assembly 123 is inserted along the gap 124, which complicates the assembly operation. Casing 1 has an open-end configuration allowing air to be forced through the spacing between the high-voltage plate 12 and ground plate 10. Slight noises generated by the electrical discharge are amplified by this configuration. Furthermore, heat is generated during the electrical discharge, causing the electrode plates to heat up. For example, the surface of the ground electrode plate (or rod) of conventional air conditioning-type corona dischargers reaches temperatures as high as 80.degree. C. after continuous use over an extended period of time; consequently, these conventional corona dischargers typically cannot he used continuously for more than 24 hours if damage is to be avoided.